JP2002335399A - Processing, device and electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for executing anticounterfeit detection that can attain a quick first page output time. SOLUTION: The processing method of this invention includes a step (204) of acquiring a high resolution image signal of an object, steps (208, 209) of acquiring a low resolution image signal of the object, and a step (218) of executing a correction processing for the low resolution image signal when the signal expresses an image of a selected type.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to anti-counterfeiting detection (ACD) of currency and transferable securities, and more particularly to such detection used in copiers and printers such as electrophotography, ink jets, and the like.

[0002]

2. Description of the Related Art ACD hardware and software are disclosed in U.S. Pat. No. 5,533, incorporated herein by reference.
No. 3,144,144.

In copiers, printers and facsimile machines having a high resolution scanner, the scanner provides a fast first copy output time by allowing simultaneous scanning and printing. In such a device with an ACD, maintaining fast fast copy output time at the same time can be costly. In particular, to achieve this, an internal buffer for acquiring high-resolution data must be maintained. The size of these buffers depends on the amount of data required by the ACD algorithm. These devices also have the problem that the currency is partially printed before detection.

[0004]

Accordingly, it would be desirable to have a method and apparatus for performing ACD that also allows for fast first page output time.

[0005]

The processing according to the present invention comprises the steps of obtaining a high-resolution image signal of an object, obtaining a low-resolution image signal of the object, and obtaining the low-resolution image signal. Performing a corrective action when representing a selected type of image.

The apparatus of the present invention includes a source of a high resolution image signal of the object, a source of a low resolution image signal of the object, and the low resolution image signal representing an image of a selected type. A corrective device for performing a corrective action.

Another aspect of the present invention is a low-resolution scanner having a low-resolution output image signal of an object, a high-resolution scanner having a high-resolution output image signal of the object, and the low-resolution output image signal having a low-resolution output image signal. An electrophotographic apparatus having a corrective device for performing corrective action when representing a selected type of image, and an electrophotographic printer.

[0008]

FIG. 1 shows an embodiment of the present invention.
The document 100 is located on a platen (not shown) of a scanner 102, which may be standalone or part of a system such as an electrophotographic device. Scanner 10
2 includes an added low-resolution image forming apparatus 108 (for example, a digital camera for forming a platen image) and a normally existing high-resolution image forming apparatus 109 (for example, forming only a small portion of the platen 107 at a time). CC to do
D device). Signals from both image forming devices 108 and 109 are transmitted to printer 1 which may be, for example, a local printer, a network printer, or the like.
06. The printer 106 may be a stand-alone printer, or may be an electrophotographic or non-electrophotographic (eg, inkjet) copier, or part of a facsimile (fax) machine. Alternatively, a high resolution signal may be received and acquired at input port 140 from a remote analog or digital source. The low-resolution signal can be obtained by low-pass filtering the high-resolution signal (analog source) or by performing decimation (digital source).

The details of the printer 106 are described in US Pat.
No. 991,201.
The image processing device 114 receives a signal from the scanner 102 or the front end 140 and generates a color image. The digital signals representing the blue, green and red density signals of the image are converted by the image processing unit into four bitmaps: yellow (Y), cyan (C), magenta (M) and black (K). Is done. This bitmap represents the exposure value required for each color component of the pixel. Image processing device 11
4 includes a low pass filter, a decimator, a shading correction unit, an under color removal unit (UCR), a masking unit, a dithering unit, a gray level processing unit, and other image processing subsystems known in the art. Is also good. Image processing device 114
Can store bitmap information of successive images or operate in a real-time mode.

At stage A, a first color toner is formed on a belt or drum 116. The photoconductive member generally has a multilayer structure, and includes a drum having a substrate, a conductive layer, an optional adhesive layer, an optional hole blocking layer, a charge generation layer, and a charge transport layer (all not shown). It is preferred that This drum is charged by the charging unit 101. Raster output scanner (ROS) 120 controlled by image processing unit 114
Draws a first color image by selectively erasing the charge on the drum 116. The ROS 120 renders image information for each pixel. Note that a discharged area development (DAD) in which a discharged portion is developed with toner may be used, or a charged area development (CAD) in which a charged portion is developed with toner may be used. After the electrostatic latent image has been recorded, drum 116 advances the electrostatic latent image to development station 103. A dry developing material is supplied by the developing station 103, and the latent image is developed. In the case of CAD development, the toner particles are attracted to the photoconductive surface because the polarity of the charge on the toner particles is opposite to the polarity of the charge on the photoconductive surface. The latent image is developed with less than a single layer of toner particles. On average, uniformity of development means that the toner particles are approximately adjacent. The developing station 103 preferably uses a small-sized toner having an average particle size of 5 μm.

The drum 116 and the intermediate member, that is, the belt 11
By applying an electrical bias between zero and zero, the developed image becomes a soft, low surface energy intermediate member 11
0 is transferred electrostatically. The residual toner on the drum 116 is removed by the cleaner 104. Intermediate member 11
0 may be either a roll or an endless belt having a conductive substrate and a flexible overcoat. The path of the belt is defined by a plurality of internal rollers. In the immediate vicinity of the toner image is an optional heating element 1
32, the toner particles existing on the surface are softened by heat. The softened toner particles pass through the film layer forming station 130. Station 130 is a heated roller (not shown) that contacts the softened toner image
And a supporting pressure roll (not shown) behind the intermediate member 110. The film forming station 130 spreads the softened toner particles into a thin film such that the small gaps between adjacent toner particles are covered with toner without deteriorating the image. The flow of toner required to cover the space between the toner particles is very small. Ideally, the film forming station should form a film of the desired thickness (approximately 1 μm) regardless of local toner coverage. One way to achieve this is to have the heated roller spontaneously separate from the intermediate belt 110 at the desired thickness. One way to achieve this requirement would be to use an intaglio roll for a heated roller (not shown).

At the stage B shown in FIG. 1, a second color is formed in the same manner as described above. The drum 116 is charged by the charging unit 101 and then the ROS 120
Is exposed according to the bitmap information of the image of the second color. After the electrostatic latent image is recorded, the drum 116
Advances the electrostatic latent image to development station 103.
The developing station 103 supplies a dry developing material having a second color toner to develop the latent image.

The developed image is transferred to the intermediate member 1 by an electric bias voltage between the drum 116 and the belt 110.
The remaining toner on the drum 116 is removed by the cleaner 104 electrostatically. The developed second color image is overlaid on the previous first color image. Heat from optional heater 132 softens the toner particles. The softened toner particles on intermediate member 110 pass through heated film forming station 130,
The film forming station 130 spreads the softened toner particles into a thin film without deteriorating the image.

In stages C and D, this process is repeated for the next two colors. A multilayer image is formed by superimposing black, yellow, magenta, and cyan toners. This full color proceeds to the transfer fusing stage E.

The transfer fusing nip 134 shown in FIG.
In the above, by applying heat and pressure between the heated roll 135 behind the intermediate belt 110 and the supporting pressure roll 136 behind the recording sheet, a multilayer full-color film image is formed on the recording sheet or paper 126. It is transferred and melted. Further, on the back surface of the recording sheet 126, there is a case where a toner image previously transferred as a result of a preceding image forming operation, that is, a double-sided operation is present. When the recording sheet 126 passes through the transfer melting nip 134, a multilayer toner film adheres to the surface of the recording sheet 126, and the attractive force between the sheet 126 and the toner film increases the surface energy of the toner film and the flexible intermediate member 110. The multi-layer toner film is transferred to the recording sheet 126 as a full-color image because the attraction is larger than the attractive force between the lower surface. The transferred and fused image is fixed as it passes through the transfer and fusion nip 134 and is cooled to a temperature below the softening temperature of the toner material. Following the cleaning of the residual toner from the intermediate belt 110 by the cleaner 106, a cycle for forming the next document is started.

Usually, the scanner 102 or the image processing apparatus 1
Within 14 is software that performs the operations shown in FIG. In a first step 200, the user places the document 100 on the platen 107. For example, another image acquisition method, such as a user arranging a plurality of sheets on a sheet feeding device (not shown), can be used. In particular, as shown at step 201, a digital document signal may be input via a digital front end, for example, front end 140. Next, the user selects a copy, fax or print by clicking on the appropriate icon (not shown), as shown in step 202. At step 208, low resolution image forming device 108 quickly provides a signal representative of the entire platen. As shown in step 209,
If a document is input via the front end, decimation (digital signals) or low-pass filtering (analog signals) will quickly produce a low resolution image. The hardware or software for performing this may be in image forming processor 114. Next, at step 210, an ACD analysis is performed, for example, as shown in US Pat. No. 5,533,144, which is incorporated herein by reference. Any other ACD hardware or software device and method may be used. Simultaneously with the steps described above, and immediately after step 202, in step 204, copy, The fax or print function is started. The result is sent to processing step 214, and the result of the ACD is also sent to processing step 214 as indicated by step 212. Processing step 214 includes, after applying appropriate image processing,
Prepare the document for printing. Appropriate image processing includes
Scaling, halftoning, color correction, etc., and the results are sent to decision step 216, where
It is determined whether currency and / or transferable securities or the like have been detected. If yes, step 218
The visual data is invalidated, preferably before a portion of the currency is printed. As a result, the printer 106 does not perform the original printing, such as printing as “invalid”, printing with only one color, or completely stopping the printing (corrective action). If no currency is detected, the printer prints document 100, as shown at step 220.

It should be appreciated that by adding an inexpensive low-resolution imaging device 108 to the scanner 102, ACD can be performed quickly, thereby preventing even partial printing of currency. This rapidity is due to the fact that the data from the low-resolution image forming device 108 is less than the data from the high-resolution image forming device 109, and that the ACD
This is because the software does not require high resolution data.

Although the present invention has been described in detail with reference to preferred embodiments, it is not intended that the invention be limited to these specific preferred embodiments, processing steps, sequences or final configurations shown in the drawings. Will be understood. On the contrary, the intent is to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims. Further, it is claimed that the methods and apparatus of the present invention have similar results.
Other methods and / or devices may be used.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is a flowchart of the operation of FIG. 1;

[Explanation of symbols]

 Reference Signs List 100 Document 102 Scanner 106 Printer 108 Low-resolution image forming apparatus 109 High-resolution image forming apparatus 114 Image processing apparatus 140 Front end

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C061 AP03 AP04 AQ05 AQ06 HJ06 HN23 2H134 NA05 NA14 NA43 5C077 LL14 MP08 PP33 PP55 TT06

Claims (8)

[Claims] Acquiring a high-resolution image signal of the object; acquiring a low-resolution image signal of the object; wherein the low-resolution image signal represents an image of a selected type. Performing a corrective action. 2. The process according to claim 1, wherein said corrective action includes stopping said high resolution image signal obtaining step. 3. The process according to claim 1, wherein said remedial action comprises invalidating said high resolution image signal. A source of a high-resolution image signal of the object; a source of a low-resolution image signal of the object; and correcting if the low-resolution image signal represents an image of a selected type. And a corrective device for performing the action. 5. The apparatus of claim 4, wherein the remedial action comprises stopping acquisition of the high resolution image signal. 6. A low-resolution scanner having a low-resolution output image signal of the object, a high-resolution scanner having a high-resolution output image signal of the object, and wherein the low-resolution output image signal is of a selected type. An electrophotographic apparatus comprising: a corrective device that performs corrective action when representing an image; and an electrophotographic printer. 7. The apparatus of claim 6, wherein the remedial action includes shutting down the printer. 8. The apparatus according to claim 6, wherein said printer has at least one station.